This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. More than half of the proteins in a genome contain metals, which have catalytic and/or structural roles. They therefore play a significant part in a considerable number of physiological functions. This proposal primarily focuses on the visualization of conformations and structural changes of (i) Cu-enzymes and their complexes of the denitrification pathway and (ii) proteins involved in neurodegenerative diseases due to their susceptibility to aggregate, here with a particular emphasis on Cu, Zn superoxide dismutase. In the absence of any structural information SAXS can provide valuable ab initio 3D shapes at low to medium resolution. Yet our complementary crystallographic work will allow us to exploit the scattering data meaningfully in particular in view of conformational changes or associations of molecules whose individual structures are known.